Tom Daley faces missing out on an Olympic medal unless he reduces his media commitments, according to British Diving's performance director Alexei Evangulov.
The former Russia coach made the stark warning to teenager Daley with just over five months before he is set to be one of Great Britain's most high-profile hopes in London.
Evangulov believes, however, that the 17-year-old is likely to miss out on a podium place unless he matches the preparations of his Chinese rivals, who he claimed train "three times harder".
"I can't stop it," Evangulov said of Daley's media and sponsorship commitments.
"If I had power over this, I would restrict it. Sometimes it hinders our preparations but I can't do anything about it."
When asked if it could affect Daley's hopes in London, he bluntly said: "Yes, it does.
"If you look at the Chinese, they work three times harder. That's the only secret. Just work hard.
"I know how the Chinese are training and they work much harder. If you compare them to Thomas, he has many commitments in his media activities.
"He's very active, not like the Chinese. The Chinese have restricted their divers and I support them on this. I would recommend Tom to make not so many commitments to the media."
Evangulov also claimed that Daley's fifth placing at last year's World Championships were a true reflection of his standing in the 10metre platform.
Daley shot to fame when he became Britain's first individual diving world champion at the age of 15 in 2009, but Evangulov warned that performance was not indicative of his status in a discipline dominated by Qui Bo and his Chinese team-mates.
"Fifth. That really was his rating at that moment," he told reporters at a training camp in Southend today.
"We are working hard to try to raise his rating position.
"The people in Great Britain are mistakenly convinced that he [Daley] is the best in the world, but he is not. He's very strong and he's one of the best, but he is not the best."
While Evangulov has criticised Daley's schedule he did admit he has some say in the teen's workload outside the pool.
The Russian has also prevented divers from speaking to the media two weeks before a meet, apart from official British Swimming media days, and added: "Every quarter, his agency send me his list of appearances for the next three months and I go through it with them and say: 'This is okay, this is okay, but this is not'."
Daley, who has claimed previously he would like to be a television presenter after his diving career, will test himself against the best at next week's FINA World Cup at the Olympic Aquatic Centre.
It will be Daley's first international competition since last July's World Championships as the top-level meets begin in earnest again before the Olympics.
Daley's media commitments are likely to create a heavier burden as London draws nearer, but the Plymouth diver is adamant he can juggle his commitments.
"I don't think that is the case, because I don't do any media now that affects my training at all," he said.
"Leading into competition I am on complete media lock-down - I only have a media day that is organised through British Swimming, so literally I am not allowed to talk to anyone in the lead-in to big competitions.
"So it is definitely very controlled, now."